Continuity mistake: As Ock climbs the building with Aunt May, a girl is on the phone and feels the trembles. She hangs up the phone and gets up to look out the window. At the desk in front of her, there is an employee helping a customer. As the first girl goes to the window, the customer gets up to leave. The tentacle crashes through the side of the building, the camera pans out and the employee helping the customer is away from her desk, the chair is pushed in and the phone is off the receiver.
Audio problem: Just before Aunt May does her hero speech she tells Peter that he 'Did a very brave thing, telling me, and I'm proud'. There is a pause between each clause of the sentence and the 'Telling me' line is obviously dubbed, the shot is from behind but the sound of the line is different.
Audio problem: When Aunt May gives Peter his birthday money, before she says, "Can you believe that it's two years next month since he was taken?", we see her from the side, and the motion of her jaw shows that her lips are moving before she speaks. When she says, "Were I to face the one responsible.", there's another shot of her from the side, and as she continues, ".for what happened", her jaw doesn't move at all. In the same shot, when she says, "Oh, I don't know what I'd do", once again the motion of her jaw show that her lips are moving before she speaks.
Continuity mistake: On the way to the play when Spider-Man is chasing the criminals in the car, the passenger is using a shotgun which switches to an automatic weapon which then switches back to a shotgun in a matter of seconds. There is no time for him to switch the guns that fast in the scene.
Continuity mistake: When Peter is being fired from his pizza place job, there is a clock behind him. While the clock is on Peter the second hand is near the 4. The shot then changes to the boss and then goes back to Peter about 10 seconds later, so the second hand should be on the 6 or the 7, but it is up at the 2.
Continuity mistake: In the scene where Aunt May is outside her house, packing things into boxes, we see a close-up of her holding what appears to be a large black leather shoe at upper chest level. The next shot is a wide shot of the yard, and now she's holding it in a different position near waist level.
Continuity mistake: When John Jameson and Mary Jane are walking down the stairs during John's celebration party, there are two people halfway down the staircase standing by themselves. When it does the closeup of John and Mary Jane, there are four people now standing in that spot.
Factual error: The only elevated trains in Manhattan are Metro North that goes to Connecticut and the N, Q, R, W line that goes to Brooklyn/Queens, and that line goes over a bridge. None of these trains are elevated in mid-Manhattan; and most certainly, the end of the subway line would not just be a big metal "bumper" that leads into the water.
Factual error: Harry stumbles onto his dad's secret room and it is free of dust except for a few cobwebs. While there may have been no human activity in the room for almost two years, there were holes in the room that let sunlight, air, and insects/arachnids in, therefore there must have been airflow. With the airflow, dust or dirt should have entered the room and collected on the items.